Search results
Results from the WOW.Com Content Network
A-DNA is thought to be one of three biologically active double helical structures along with B-DNA and Z-DNA. It is a right-handed double helix fairly similar to the more common B-DNA form, but with a shorter, more compact helical structure whose base pairs are not perpendicular to the helix-axis as in B-DNA.
Non-B DNA can be classified into several types, including A-DNA, Z-DNA, H-DNA, G-quadruplexes, and Triplexes (Triple-stranded DNA).. A-DNA is a right-handed double helix structure for RNA-DNA duplexes and RNA-RNA duplexes that is less common than the more well-known B-DNA structure.
Z-DNA is one of the many possible double helical structures of DNA. It is a left-handed double helical structure in which the helix winds to the left in a zigzag pattern, instead of to the right, like the more common B-DNA form. Z-DNA is thought to be one of three biologically active double-helical structures along with A-DNA and B-DNA.
DNA exists in many possible conformations that include A-DNA, B-DNA, and Z-DNA forms, although only B-DNA and Z-DNA have been directly observed in functional organisms. [14] The conformation that DNA adopts depends on the hydration level, DNA sequence, the amount and direction of supercoiling, chemical modifications of the bases, the type and ...
The structure a DNA molecule depends on its environment. In aqueous enviromnents, including the majority of DNA in a cell, B-DNA is the most common structure. The A-DNA structure is dominates in dehydrated samples and is similar to the double-stranded RNA and DNA/RNA hybrids. Z-DNA is a rarer structure found in DNA bound to certain proteins.
Exon sequences consist of coding DNA and untranslated regions (UTRs) at either end of the mature mRNA. The total amount of coding DNA is about 1-2% of the genome. [20] [18] Many people divide the genome into coding and non-coding DNA based on the idea that coding DNA is the most important functional component of the genome.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
[2] [3] The mRNA sequence is determined by the sequence of genomic DNA. [4] In this context, the standard genetic code is referred to as translation table 1. [3] It can also be represented in a DNA codon table. The DNA codons in such tables occur on the sense DNA strand and are arranged in a 5 ′-to-3 ′ direction.